[pve-devel] applied: [PATCH qemu 1/1] PVE Backup: allow passing max-workers performance setting

[Wolfgang Bumiller]

applied this one, thanks

On Mon, Oct 03, 2022 at 03:52:04PM +0200, Fiona Ebner wrote:
> For query-proxmox-support, add an indication that it's possible to use
> the setting.
> 
> For now, the other two BackupPerf settings are not exposed:
> 
> * use-copy-range: would need to be implemented by the backup-dump
> block driver first, and in fact, the default for backup was changed,
> because it wasn't as fast for backup in QEMU, see commit
> 6a30f663d4c0b3c45a544d541e0c4e214b2473a1.
> 
> * max-chunk: enforced to be at least the backup cluster size, which is
> 4 MiB for PBS and otherwise maximum of source and target cluster size.
> And block-copy has a maximum buffer size of 1 MiB, so setting a larger
> max-chunk doesn't even have an effect. To make the setting sensibly
> usable the check would need to be removed and optionally the
> block-copy max buffer size would need to be bumped. I tried doing just
> that, and tested different source/target combinations with different
> max-chunk settings, but there were no noticable improvements over the
> default "unlimited" (resulting in 1 MiB for block-copy).
> 
> Signed-off-by: Fiona Ebner <f.ebner at proxmox.com>
> ---
>  block/monitor/block-hmp-cmds.c |  4 +++-
>  pve-backup.c                   | 18 +++++++++++++-----
>  qapi/block-core.json           |  9 +++++++--
>  3 files changed, 23 insertions(+), 8 deletions(-)
> 
> diff --git a/block/monitor/block-hmp-cmds.c b/block/monitor/block-hmp-cmds.c
> index 0502f42be6..cc231ec3f2 100644
> --- a/block/monitor/block-hmp-cmds.c
> +++ b/block/monitor/block-hmp-cmds.c
> @@ -1049,7 +1049,9 @@ void coroutine_fn hmp_backup(Monitor *mon, const QDict *qdict)
>          false, false, // PBS encrypt
>          true, dir ? BACKUP_FORMAT_DIR : BACKUP_FORMAT_VMA,
>          false, NULL, false, NULL, !!devlist,
> -        devlist, qdict_haskey(qdict, "speed"), speed, &error);
> +        devlist, qdict_haskey(qdict, "speed"), speed,
> +        false, 0, // BackupPerf max-workers
> +        &error);
>  
>      hmp_handle_error(mon, error);
>  }
> diff --git a/pve-backup.c b/pve-backup.c
> index 2e22030eec..e9aa7e0f49 100644
> --- a/pve-backup.c
> +++ b/pve-backup.c
> @@ -55,6 +55,7 @@ static struct PVEBackupState {
>          bool starting;
>      } stat;
>      int64_t speed;
> +    BackupPerf perf;
>      VmaWriter *vmaw;
>      ProxmoxBackupHandle *pbs;
>      GList *di_list;
> @@ -492,8 +493,6 @@ static void create_backup_jobs_bh(void *opaque) {
>      }
>      backup_state.txn = job_txn_new_seq();
>  
> -    BackupPerf perf = { .max_workers = 16 };
> -
>      /* create and start all jobs (paused state) */
>      GList *l =  backup_state.di_list;
>      while (l) {
> @@ -513,8 +512,9 @@ static void create_backup_jobs_bh(void *opaque) {
>  
>          BlockJob *job = backup_job_create(
>              NULL, di->bs, di->target, backup_state.speed, sync_mode, di->bitmap,
> -            bitmap_mode, false, NULL, &perf, BLOCKDEV_ON_ERROR_REPORT, BLOCKDEV_ON_ERROR_REPORT,
> -            JOB_DEFAULT, pvebackup_complete_cb, di, backup_state.txn, &local_err);
> +            bitmap_mode, false, NULL, &backup_state.perf, BLOCKDEV_ON_ERROR_REPORT,
> +            BLOCKDEV_ON_ERROR_REPORT, JOB_DEFAULT, pvebackup_complete_cb, di, backup_state.txn,
> +            &local_err);
>  
>          di->job = job;
>          if (job) {
> @@ -584,7 +584,9 @@ UuidInfo coroutine_fn *qmp_backup(
>      bool has_config_file, const char *config_file,
>      bool has_firewall_file, const char *firewall_file,
>      bool has_devlist, const char *devlist,
> -    bool has_speed, int64_t speed, Error **errp)
> +    bool has_speed, int64_t speed,
> +    bool has_max_workers, int64_t max_workers,
> +    Error **errp)
>  {
>      assert(qemu_in_coroutine());
>  
> @@ -914,6 +916,11 @@ UuidInfo coroutine_fn *qmp_backup(
>  
>      backup_state.speed = (has_speed && speed > 0) ? speed : 0;
>  
> +    backup_state.perf = (BackupPerf){ .max_workers = 16 };
> +    if (has_max_workers) {
> +        backup_state.perf.max_workers = max_workers;
> +    }
> +
>      backup_state.vmaw = vmaw;
>      backup_state.pbs = pbs;
>  
> @@ -1089,5 +1096,6 @@ ProxmoxSupportStatus *qmp_query_proxmox_support(Error **errp)
>      ret->pbs_dirty_bitmap_migration = true;
>      ret->query_bitmap_info = true;
>      ret->pbs_masterkey = true;
> +    ret->backup_max_workers = true;
>      return ret;
>  }
> diff --git a/qapi/block-core.json b/qapi/block-core.json
> index 89875f309c..43281aca79 100644
> --- a/qapi/block-core.json
> +++ b/qapi/block-core.json
> @@ -833,6 +833,8 @@
>  #
>  # @encrypt: use encryption ((optional for format 'pbs', defaults to true if there is a keyfile)
>  #
> +# @max-workers: see @BackupPerf for details. Default 16.
> +#
>  # Returns: the uuid of the backup job
>  #
>  ##
> @@ -851,7 +853,9 @@
>                                      '*format': 'BackupFormat',
>                                      '*config-file': 'str',
>                                      '*firewall-file': 'str',
> -                                    '*devlist': 'str', '*speed': 'int' },
> +                                    '*devlist': 'str',
> +                                    '*speed': 'int',
> +                                    '*max-workers': 'int' },
>    'returns': 'UuidInfo', 'coroutine': true }
>  
>  ##
> @@ -906,7 +910,8 @@
>              'pbs-dirty-bitmap-savevm': 'bool',
>              'pbs-dirty-bitmap-migration': 'bool',
>              'pbs-masterkey': 'bool',
> -            'pbs-library-version': 'str' } }
> +            'pbs-library-version': 'str',
> +            'backup-max-workers': 'bool' } }
>  
>  ##
>  # @query-proxmox-support:
> -- 
> 2.30.2